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Down-and up-conversion processes in Nd^(3+)/Yb^(3+)co-doped sodium calcium silicate glasses with concomitant Yb^(2+)assessment

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Journal of Rare Earths 2023年第3期41卷 342-348,I0001页

作者： R.f.Muniz V.S.Zanuto M.S.Gibin J.V.Gunha A.Novatski J.H.Rohling A.N.Medina M.L.Baesso Departament of Science State University of MaringáAv.Reitor Zeferino Vaz s/nGoioerê87360-000PRBrazil Departament of Physics State University of MaringáAv.Colombo 5790Maringá87020-900PRBrazil Departament of Physics State University of Ponta GrossaAv.Carlos Cavalcanti4748Ponta Grossa 84030-900PRBrazil

Novel Nd^(3+)/Yb^(3+)co-doped sodium calcium silicate glasses were prepared by melting quenching method:Spectroscopic study was carried out as a function of doping content by fixing sensitizer(Nd^(3+))concentration to 0.2 mol%and adjusting activator(Yb^(3+))from 0 to 1.0 mol%.The energy transfer(ET)mechanisms between Nd^(3+)and Yb^(3+)are discussed based on their energy levels and excitation powerdependence emission *** show that the presence of Yb^(2+)might be considered for the Nd^(3+)-free and co-doped *** ET was confirmed by the down-conversion NIR emission spectra of the doped and co-doped samples under excitation at 808 *** mechanisms observed seem to involve only one VIS absorbed photon for each NIR emitted via direct energy transfer between^(4)f_(3/2)of Nd^(2+)and^(2)f_(5/2)of Yb^(3+)compensated by phonon assistance due to energy gap between these *** efficiency of ET increases with the ytterbium content up to almost 90%for the sample with 1 mol%of Yb2O3,which was evaluated by lifetime ***-conversion photoluminescence by exciting trivalent ions of neodymium(808 nm)and ytterbium(975 nm)is *** observed up-converted emission bands are related to the 4f-4f transitions of Nd^(3+)and the spin-forbidden 5d-4f transition of Yb^(2+).Nd^(3+)upconversion emission is observed under 975 nm excitation,presenting an almost quadratic emission dependence with power excitation,which suggests that two laser photons participate in the up-conversion(UC)process,showing that ET occurs by a phonon-assisted energy transfer and cooperative energy transfer.

关键词： Solar cells Energy transfer Glassy systems Rare earths

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商法史

Effects of varying Alx moles on structure and luminescence properties of ZnAl_(x)O_(1.5x+1):0.1 mol%Tb^(3+)nanophosphors prepared using citrate sol-gel method

2017年

作者： (意)f.卡尔卡诺

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Journal of Rare Earths 2023年第3期41卷 358-364,I0002页

作者： V.M.Maphiri L.T.Melato M.R.Mhlongo T.T.Hlatshwayo T.E.Motaung L.f.Koao S.V.Motloung Department of Physics Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Mathematics Non Destructive Testing and PhysicsVaal University of TechnologyAndries Potgieter BlvdVanderbijlpark1900South Africa Department of Physics University of PretoriaPretoria0002South Africa Department of Chemistry School of Science in the College of Science Engineering and TechnologyUniversity of South AfricaPreller StreetMuckleneuk RidgeCity of TshwaneP.O Box 392UNISA 0003South Africa Department of Chemistry Sefako Makgatho Health Science UniversityP.O.Box 94Medunsa0204South Africa Department of Physics University of the Free State(Qwaqwa Campus)Private Bag X13Phuthaditjhaba 9866South Africa Department of Chemical and Physical Sciences Walter Sisulu UniversityMthathaSouth Africa

Un-doped and ZnAl_(x)O_(1.5x+1):0.1 mol%Tb^(3+)(ZAOT)nano-powders were synthesized via citrate sol-gel *** AIx moles were varied in the range of 0.25≤x≤*** X-ray powder diffraction(XRD)data reveal that for xf mixed phases of the cubic ZnAl_(2)O_(4) and hexagonal ZnO phases,while for x>1.5 the structure consists of single phase of cubic ZnAl_(2)O_(4).The Raman and fourier-trans form infrared(fTIR)vibrational spectroscopy show the presence of vibrations emanating ZnAl_(2)O_(4) *** electron microscopy(SEM)and transmission electron microscopy(TEM)show the presence of irregular sphere at x>2.0 attributed to ZnAl_(2)O_(4).The photoluminescence(PL)spectroscopy reveals emissions from both the host and Tb^(3+)*** from Tb^(3+)are observed at 382,414,439,458 nm and 489,545,585,621 nm,which were attributed to the^(5)D_(3)→^(7)f_(6,5,4,2) and ^(5^)D_(4)→^(7)f_(6,5,4,3),*** results confirm that the Tb^(3+)occupation site depends on the Alx *** International Commission on Illumination(CIE)colour chromaticity shows that the emission colour can be tuned from blue to green by varying the AIx moles.

关键词： Citrate sol-gel ZnAl_(2)O_(4)/ZnO Tb^(3+)-doped Al_(x)moles Photoluminescence Rare earths

Antibiotics Resistance Pattern and Plasmid Profiling of <i>Edwardsiella tarda</i>Isolated from <i>Heterobranchus longifilis</i>

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Journal of Biosciences and Medicines 2018年第4期6卷 95-105页

作者： f. C. Ogbonne E. R. Ukazu f. C. Egbe Nigerian Institute for Oceanography and Marine Research Lagos Nigeria

A study was carried out to investigate antibiotic resistance patterns and plasmid profiling of Edwardsiella tarda isolated from farmed-cultured Heterobranchus longifilis in Lagos State, Southwest of Nigeria. A total of 44 Edwardsiella isolates were recovered from 80 fish samples collected from the 10 fish farms using selective random stratification. It was observed that Edwardsiella tarda isolates were 100% resistant to Amoxicillin, Chloranphenicol, Levofloxacin, Streptomycin and 90% resistant to Nalidixic Acid respectively. All the isolates were 100% susceptible to Spectinomycin and Ciprofloxacin, while Ofloxacin, Gentamycin, and Pefloxacin vary in their level of susceptibility with 90%, 80% and 70% sensitivity respectively. Conversely, 8 out of 10 fish farm locations studied were observed to have antibiotic-resistant strains, and 5 out of 8 drug-resistant strains were found to carry plasmid and the sizes of the plasmid ranges between 20.027 kb to 23.130 kb. The plasmid after treatment with mitomycin C and ethidium bromide were lost during the process of plasmid curing confirming that the multiple drug resistant exhibited by the isolates was plasmid mediated. There are fewer studies on antibiotic resistance in Edwardsiella tarda from aquaculture enterprises and this study provides further support to the view that there is a potential risk of transfer of resistant bacteria and their genes to human pathogen through the food chain. Although, in Nigeria there is no antibiotic product registered for aquaculture usage, yet fish farmers use them off-label for bacterial diseases prevention.

关键词： Edwardsiella tarda Plasmid Profiling Antibiotic Resistance Heterobranchus longifilis

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保德河盆地莫里页岩的固态核磁共振特征

地质地球化学 1995年第3期23卷 29-33页

作者： f.P.Miknis 吴元江苏油田地科院

对怀俄明州保德河盆地莫里页岩的一组生油岩样品进行了固态13C核磁共振（NMR）测量。这项研究的目的是几CP／MAS13CNMR测量来监测由埋深引起的干酪根碳结构的变化。NMR测量样品的现今埋深为3000～11500英尺1）。由于总有机碳含量主要为... 详细信息

对怀俄明州保德河盆地莫里页岩的一组生油岩样品进行了固态13C核磁共振（NMR）测量。这项研究的目的是几CP／MAS13CNMR测量来监测由埋深引起的干酪根碳结构的变化。NMR测量样品的现今埋深为3000～11500英尺1）。由于总有机碳含量主要为（1～2）Wt％，在13CNMR测量中使用了大容量的样品旋转器。用HCI清洗样品能提高13C谱图的质量。干酪根的芳香度随理深的增加而增加，在深度超过10000英尺时，由于干酪根中残留的脂肪族碳很少，几乎不能再生油。结合NMR和生油岩评价数据，得到了氢聚散的估算结果。计算表明，约有20％的干酪根转化为烃类，由于芳构化和缩合反应，释放出足够的氢，而使产物稳定下来。

关键词：页岩岩样固态核磁共振

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托业听力本领书

The industrial dynamics of water innovation:A comparison between China and Europe

丛书名：国际交流英语考试标准版

2003年

作者：（美）Alan f.Wright

本书分听力题型演练、全真模拟测验等内容。囊括TOEIC听力测验4大题型，提供了400道精华练习题。书中题型、题量、难度均符合考试需要。

ISBN: (纸本)7111116666

本书分听力题型演练、全真模拟测验等内容。囊括TOEIC听力测验4大题型，提供了400道精华练习题。书中题型、题量、难度均符合考试需要。

关键词：英语听说教学水平考试

来源：畅想之星图书光盘版（南... 评论

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International Journal of Innovation Studies 2018年第1期2卷 14-32页

作者： MariúAbritta Moro Ursula S.McKnight Barth f.Smets Yang Min Maj Munch Andersen Department of Environmental Engineering Technical University of DenmarkBygningstorvet 1152800 Kgs.LyngbyDenmark Sino-Danish Center for Education and Research(SDC) Niels Jensens Vej 28000 Aarhus CDenmark Research Center for Eco-Environmental Science.Chinese Academy of Science 18 Shuangqing RoadHaidian DistrictBeijingChina Department of Management Engineering Technical University of DenmarkDiplomvej Building 3722800 Kgs.LyngbyDenmark

The expansion of the green economy agenda has increased the attention on ecoinnovations globally,with issues related to water stress identified as one of the major bottlenecks for sustainable economic *** evolutionary economic theory,this study investigates the industrial dynamics of the water sector,comparing China and Europe using patent *** comparison feeds into the“catching up”literature,addressing the challenges of the“green economy”agenda in different regions in various stages of *** highlight the neglected micro-dynamics of water innovation,investigating the roles of different innovators in the development of water technological trajectories,with a special focus on water innovations closely related to climate change adaptation and mitigation *** water innovators(universities)were found to be more important in China than in *** were also identified between Europe and China;big companies were found to be the main innovative leaders with no substantial changes documented over the timeframe ***,the finding implies a rapid Chinese technological catching up of water technologies in the last three decades,where our research has pointed towards the role of redirection of Chinese policies with a stronger focus on sustainable *** analysis,overall,sheds light on the state and nature of the globalizing green growth agenda.

关键词： Water innovation Eco-innovation Evolutionary economics Knowledge institutions Business demography

Anti-cancer liposomal chemophototherapy using bilayer-localized photosensitizer and cabazitaxel

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Nano Research 2022年第5期15卷 4302-4309页

作者： Boyang Sun Sanjana Ghosh Xuedan He Wei-Chiao Huang Breandan Quinn Meiling Tian Dushyant Jahagirdar Moustafa T.Mabrouk Joaquin Ortega Yumiao Zhang Shuai Shao Jonathan f.Lovell Translational Medicine Center The First Affiliated Hospital of Zhengzhou UniversityZhengzhou 450000China Department of Biomedical Engineering University at BuffaloState University of New YorkBuffaloNY 14260USA Department of Anatomy and Cell Biology McGill UniversityMontrealQuebec H3A0C7Canada School of Chemical Engineering and Technology Tianjin UniversityTianjin 300000China

Photodynamic therapy(PDT)is a non-invasive tumor ablation modality that can be enhanced in combination with concurrent ***,we demonstrated that liposomes containing a bilayer-anchored photosensitizer(porphyrin-phospholipid;PoP)can be loaded with drugs in their aqueous core to improve drug delivery and tumor ablation upon target tissue irradiation with *** the present work,we demonstrate that this concept can be extended to drugs loaded within the hydrophobic bilayer of ***(CTX)is a potent second generation taxane anti-cancer drug that was loaded in the bilayer of liposomes also containing 0.1 molar%PoP,generating CTX-loaded PoP liposomes(CTX-PoP-Lip).CTX-PoP-Lip showed unilamellar vesicle morphology,and exhibited integrity in storage and serum,while maintaining drug stability under laser *** vitro cell killing evaluation showed that red-light laser irradiation induced cytotoxicity in cells incubated with CTX-PoP-Lip,compared to control *** vivo pharmacokinetic analysis revealed that following intravenous administration to mice,CTX and PoP exhibited somewhat altered circulation profiles,suggesting that the CTX may have exchanged with serum factors in ***,when a single treatment of CTX-PoP-Lip with laser irradiation was administered to mice bearing human MIA Paca-2 tumors,tumors were effectively ablated whereas the equivalent chemotherapy and PDT monotherapies were *** results demonstrate the versatility of liposome delivery systems for achieving tumor ablation with chemophototherapy.

关键词： photodynamic therapy cabazitaxel liposome chemotherapy porphyrin-phospholipid

Stress-rupture behavior of a Re-containing Ni-base single crystal superalloy at high temperatures

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Journal of Materials Science & Technology 2023年第32期163卷 237-244页

作者： G.L.Wang D.Q.Qi J.L.Liu J.D.Liu J.G.Li Y.Z.Zhou X.f.Sun Institute of Metal Research Chinese Academy of SciencesShenyang 110016China

A Re-containing Ni-base single crystal superalloy was used to investigate the elementary processes associated with stress-rupture behavior at different temperatures where theγʹrafting *** 900°C,the rupture behavior is mainly determined by the multiplication of dislocations within the wideningγchannels,which is closely linked with the propagation of microcracks along the inherentγ/γʹ*** rapid formation of lamellaγ/γʹraft structure,along with the developed-well interfacial dislocation networks,and its elastic instability are primarily responsible for the rupture behavior at 1100°*** is a clear curvature tendency in the Larson-Miller plot of stress-rupture lifetime in relation to stress at high *** indicates that the influence extent ofγʹrafting on stress-rupture behavior is sensitive to the acting conditions of temperature and stress.

关键词： Ni-based single crystal superalloy Re effect γʹrafting Stress-rupture behavior Elementary process Larson-Miller plot